textproduct: Albany

WHAT HAS CHANGED

SPC expanded the Slight Risk (Level 2 of 5) slightly further north to include all of the eastern Catskills, Mid-Hudson Valley, south- central Taconics, the southern reaches of the Capital District, south- central Berkshires and Litchfield County, CT. The Marginal Risk (Level 1 of 5) includes the rest of the forecast area, except the southern Adirondacks and most of the Glens Fall Lake George Region.

Retooled hourly PoPs and weather late this pm into tonight with the timing of the front with a transition to some snow showers/flurries over the higher terrain including the western Dacks, southern Greens and northern Catskills. Also blended in some NBM90 wind gusts tomorrow afternoon with brisk west/northwest to northwest winds tonight through Saturday morning.

KEY MESSAGES

1) A strong cold front will bring gusty winds, showers, and a few strong to potentially severe thunderstorms to the region this afternoon into early tonight.

2) Continued gusty winds and unseasonably chilly conditions are expected tonight through Saturday. A coating to a few tenths of an inch of snow are possible in the high terrain late tonight into Saturday morning.

3) Dry weather with temperatures moderating to near seasonable levels late Sunday into early next week.

DISCUSSION

KEY MESSAGE 1...

As of 252 pm EDT...A strong cold front continues to approach from west- central NY and PA this afternoon, as low pressure moves towards southern Quebec. A strong positively-tilted trough mid and upper level associated with the system is moving across the eastern Great Lakes Region and the Midwest. Pre-frontal showers continue across the southern Adirondacks and w-central Mohawk Valley. Some breaks in the clouds occurred across the Capital District/Schoharie Valley earlier but stratus has increased again across most of the region. A high shear-low CAPE environment is setting up from the Mohawk Valley/Capital Region/Berkshires south and east. SPC has most of the forecast area in Marginal (Level 1 of 5) or Slight Risk (Level 2 of 5) due to some low-topped convection potentially forming that may bring some isolated damaging wind gusts to the southern portion of the forecast area.

The latest HREFS/REFS has limited mean SBCAPEs of 100-250 J/kg south of the Capital District over the mid Hudson Valley, southeast Catskills, southern Taconics, and NW CT. The 0-6 km bulk shear increases 40-60+ KT. The CAMs soundings from the 3-km HRRR/ARW-WRF show 800 hPA winds increasing to 45-50 KT with the low to mid level winds very strong. A broken line or strongly- forced line of convection is possible on some of the CAMs with the threat looking the greatest from about Hudson, NY to the I-84 corridor. The question will be if any updrafts will be tall enough to tap into these winds aloft and translate them to the sfc. At the very least, we could be looking at some gusty showers with a rumble of thunder with gusts 30-50 mph which could blow around loosely unsecured objects, and bring down some foliated large tree limbs. The the threat window looks like 3-7 pm before the showers and possibly some embedded strong/potentially severe thunderstorms move east of most of the forecast area with the front.

KEY MESSAGE 2...

Tonight, in the wake of the cold front brisk/blustery conditions occur, as west/northwest winds 10-20 mph shift to the northwest with the cold advection. Some gusts 25-35 mph will likely occur with a few isolated gusts around 40 mph funneling down the Mohawk Valley into the Capital Region, northern Taconics and the Berkshires. Some gusty winds are also possible over the northern/eastern Catskills. In the wake of the front with the mid and upper trough approaching, some upslope rain to snow showers will occur over the western Dacks and southern Greens. Some light snow accums of a coating to a few tenths of inch may occur. Some light snow showers/flurries could occur over the northern Catskills, northern Taconics and Berkshires due to upslope and lake enhanced showers. The low-level flow quickly veers to the northwest with some multi-bands of lake effect potentially grazing the northern and eastern Catskills Saturday morning. Latest NAEFS indicate H850 temp anomalies will be 1 to 2 STDEVs below normal. The actual H850 temps fall to -6C to -9C from Albany north and west into the Adirondacks to 0C to -6C readings south and east towards the I-84 corridor by daybreak Saturday. Temps will fall quickly with widespread lows in the 30s to lower 40s with some upper 20s over the south/southwest Adirondacks and southern Greens. Wind chill temps or "feels-like" temps when combining the winds with the air temps will be in the teens to mid/upper 20s over the higher terrain with mainly 30s in the valleys with some mid/upper 20s in the western Mohawk Valley. It will feel like early Winter.

Upslope and lake effect snow showers/flurries or sprinkles will end in the late morning with the subsidence inversion lowering. The brisk northwest winds will continue with chilly temps with daytime highs only in the 40s in the valleys with a few readings near 50F in the Hudson Valley and 30s to lower 40s over the hills and mtns. The winds will persist from the northwest at 10-20 mph with some gusts 25-35 mph due to the sfc pressure gradient and some deeper mixing. We increased gusts slightly blending in the latest NBM 90th percentile. The latest NBM 24-hr probs for gusts >35 mph are low from 2 am Sat to 2 am Sun, as they are only 20-40% over the northern Taconics/northern Berkshires and eastern Catskills. Gusts > 40 mph are less than 15%, so no Wind Advisories expected. Wind Chills/"Feels-like" temps will continue in the 20s and 30s for much of the day. The winds subside fairly quickly Saturday night with the sfc high building in from the Ohio Valley over PA and NY. Lows fall into the 20s to around 30F. The growing season is over, but a widespread frost will occur across the region.

KEY MESSAGE 3...

High pressure will be overhead and nearby NY and New England to close the weekend with temps rebounding after a cold start into the mid/upper 40s to mid 50s across eastern NY and western New England with mostly sunny skies and light winds. Another chilly night is expected Sunday night with lows in the mid 20s to mid 30s, but temps moderate to seasonal levels in the 50s to around 60F on Monday with partly to mostly sunny skies. Dry weather and seasonable temps continue through the mid week, as we monitor a potential nor'easter near the Mid Atlantic Coast during the mid week (Tue- Wed time frame).

AVIATION /18Z FRIDAY THROUGH WEDNESDAY/

Through 18Z/Saturday...Conditions vary amongst the terminals this afternoon as visible satellite shows some breaks in a largely MVFR stratus deck, forcing isolated VFR conditions, with some scattered IFR heights throughout the region. Latest scans of the ENX radar indicate the significant breaking apart of what was formerly a pre-cold frontal rainband with little threat to impact any of the terminal domains within the next couple of hours. Winds are somewhat variable (southeast to southwest directions) ahead of the incoming cold front, with sustained speeds ranging from about 3 to 11 kt with occasional gusts between 20 to 30 kt at ALB and PSF.

While eastward-translating breaks in cloud coverage could allow for additional, brief improvements in ceiling heights over the next couple of hours, the further encroachment of the cold front should reinforce the holes and force the return to consistent MVFR and possible IFR conditions. Additional batches of showers closer accompanying the cold front are beginning to fill into central New York and could impact terminals between 19-00z this afternoon and evening. However, because of the latest trends in the guidance and radar scans, confidence has become lower in the occurrence of showers at ALB, POU, and PSF. These sites were therefore given PROB30s to account for the potential of additional showers while GFL has a TEMPO given enough confidence in brief showers given their proximity to the eastern-most Great Lake. Once the cold front rips through this afternoon and this evening, fairly swift improvements to VFR ceiling heights are expected for all except PSF which could hang on to an MVFR ceiling longer into the overnight. Winds will also become very breezy behind the front, taking on a westerly and then northwesterly direction, with sustained speeds reaching 10-15 kt with gusts of 20-30 kt by the end of the 18z cycle.

Outlook...

Saturday Night to Wednesday: No Operational Impact. NO SIG WX.

ALY WATCHES/WARNINGS/ADVISORIES

CT...None. NY...None. MA...None. VT...None.